Babies always cry. Even chill babies cry. However, a baby with true colic will fit into the "rule of threes."
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Babies always cry. Even chill babies cry. However, a baby with true colic will fit into the "rule of threes."

The rule of threes is a typical diagnosing tool used by pediatricians. What this means is that your baby cries at least three days a week, cries for at least three hours in duration, and the constant crying starts when your baby is about three weeks old. If your baby fits with the rule of threes, he may have colic. If you think your baby fits with these rules, visit your pediatrician and get a true diagnose. Also, your pediatrician will be able to offer suggestions about calming the crying.